DC to DC converters are switching power supplies which convert received input power by operation of one or more switching devices to provide a controlled DC output. Various forms of DC to DC converters have been developed, including buck converters which regulate the output voltage to a level generally lower than the input voltage, as well as boost converters which can provide an output voltage higher than the input voltage level. The converter switching devices are typically operated in closed loop fashion through pulse width modulation (PWM) for voltage mode control with the PWM duty cycle being adjusted according to an output voltage feedback signal. Current mode control techniques are sometimes used in which an inner current control loop and an outer voltage control loop are used. One type of current mode control involves fixed frequency peak current mode control with a fixed slope compensation ramp added to a sensed inductor current ramp to mitigate sub harmonic switching, where the current through a converter inductor is directly controlled and the output voltage is controlled indirectly by the current loop. Changing the switching frequency for different applications, however, requires adjustment in the compensation slope. Single and multi-phase peak current mode PWM regulators have been developed which can operate over a wide range of frequencies from several tens of kilohertz through gigahertz operation, and provide a dedicated pin for connection to an external resistor or other component to adjust the compensation slope. However, operation of the DC to DC converter is thus dependent upon the external component to provide a compensation slope corresponding to the operating frequency, and incorrect selection of external components can cause a mismatch between the actual operating frequency and the compensation slope. In addition, providing a dedicated integrated circuit pin for external compensation adjustment is costly in terms of circuit board area and component costs. Accordingly, a need remains for improved DC to DC converters and PWM controllers for simplified operation over a wide range of converter switching frequencies.